Sen. Grace Poe today said expanding the country's main gateway would be the main solution to address congestion at the Ninoy Aquino International Airport (NAIA).

Poe, chairperson of the Senate committee on public services, said the government should seriously consider the unsolicited proposals of the private sector for the rehabilitation and maintenance of NAIA.

"We have the interest of the private sector to be able to help the government... We have to admit that sometimes with the help of the private sector, we can implement projects faster and especially if the consortium is composed of credible investors," Poe told reporters in a chance interview after emerging from the Senate hearing on airport congestion.

NAIA, which only has two runways, was designed to handle 30 million passengers, but travelers who used the four terminals reached almost 40 million in 2016. NAIA was also consistently tagged as one of the worst airports in the world in recent years.

A "super" consortium composed of some of the country's biggest conglomerates and GMR-Megawide have submitted to the government their unsolicited proposals separately worth P350 billion and P150 billion to upgrade the highly congested NAIA.

"For as long as there's an agreement that they will not overcharge passengers and there are certain safeguards and guidelines, I think that we should welcome as much interest to be able to rehabilitate NAIA," Poe said.

Poe likewise touted the soon-to-open Cebu international airport terminal when she recently visited the province, saying the modern design of infrastructure projects that provide passenger efficiency can be achieved if the government works closely with reputable private firms.

"I visited the Cebu airport and they are going to inaugurate the new terminal and I see the promise of that. Hopefully more [airports will be modernized] but definitely it [bidder] has to be somebody with the track record and competence to be able to do this because government is so stretched and we need investors and expertise," the senator added.

Poe's proposal also comes as the Manila International Airport Authority (MIAA) plans to rationalize operations at Manila's four airports. Terminals 1 and 3 will be exclusive to international flights while Terminal 2 and 4 will be for domestic flights, meaning some domestic operations will have to be redistributed within NAIA and Clark airport, which is some 100 kilometers north of Manila.

The senator said distributing domestic operations is only a band-aid solution.

Meanwhile, Poe said passengers should demand airline companies for a refund after it was reported that at least P250 million in unused terminal fee remains unclaimed from Cebu Pacific.

"A lot are paying the terminal fees but they don't actually take the flight, they are entitled to a refund... Sayang naman, kunin po ninyo ang pera ninyo," said Poe, who added that there should be an easier mechanism for processing of refunds.

Flag carrier Philippine Airlines and Cebu Pacific said they are processing requests for refund.